This site and game is just so badass that it needs it's own topic. Anyway have you ever played Tetris and on the site Tetris Friends?

The game site is awesome. You can create a profile and do all sorts of different computer vs human games. 1 vs 1, a 6 free for all battle, a wacky 8 free for all, retro tetris, and even several different time attack and forever tetris games (that end when you screw up)

There's also this thing called Arena where you can fight as a team or free for all against different users from all over the world. You can have up to 3 vs 3 games to a 6 free for all battle. The power ups they have just make the game even crazier.